Film-developing apparatus



ugflz, 1930- G. w. HOPKINS FIL DEVELOPING APPARATUS Filed Aug. 51, 19272 Sheets-Sheet l ,En/enf@ M/@M v4/gis.

Aug. 12, 1930. G. w. HOPKINS MLM DEVELOPING APPARATUS Filed Aug. 31,1927 2 Sheets-SheetV 2 56 U. 1 g fm Patented Aug. 12, 193.0

c UNITED STATES GEORGE W. HOPKINS, F CLEVELAND, OHIO FILI-DEVELOPINGAPPARATUS Application ied August 81, 1927. Serial No. 216,556.

This invention relates to a photographic film developin and fixing aparatus and has for one of its o jects to provi e an a paratus which issimple in construction,"e cient in operation and .exceptionallyinexpensive in co'st.

In the developing of photographic films after exposure, it is customaryto submerge the film in a developing solution for a suitable length oftime or until the subject upon the film is clearly visible, at whichtime the` film is transferred to a wash water and then to a fixing bathor solution. After the film has remained in the fixing solution or bathfor a suitable length of time, it is thereafter transferred to a waterwash or bath and ermitted to remain there until the film is t oroughlyfixed, after which it is removed and suitably dried for interpretation.

Considerable difficulty has been experienced in developing films,particularly during hot weather, inasmuch as the developing and fixingsolutions become too warm, due to the surrounding atmosphericconditions, and, as a result, the photographic films, during the stageof development, are Very often stained and sometimes ruined. Similardifficulties are experienced during cold weather inasmuch as thedeveloping solutions are con- 39 siderably colder, which materiallyretards the develo ing of the films, and various meth- 4 ods have eenemployed to reduce the temperature of the developing solutions in hotweather and to raise the temperature in cold weather. One of thesemethods of lowering the temperature of the developing solutions in hotweather is to place the developing tank in a tray of water containingice, but this is very unsatisfactorv inasmuch as the ternperature iscontinually changing as the ice becomes melted or when new ice isintroduced into the tray of water.

It is, therefore, one of the primary objects of this invention toprovide an apparatus having a developing solution, a fixing solution andrunning Wash water, all of which can be predeterminatelv maintained atany desired temperature irrespective of surrounding atmosphericconditions. It has been found that a temperature of about 65 Fahrenheitis the most satisfactory temperature at which to work with' thesesolutions, inasmuch as the best results are obtainable under thattemperature condition.

A further object of the invention is to provide an apparatus of the typereferred to in which running water is continually fed around the develoing and fixing tanks to maintain the solutions contained therein at apredetermined temperature and then causing the water to flow throughwash water tanks adapted to support the hotographic films after thelatter have been eveloped and fixed, so as to wash the solutions fromthe films before drying.

A further obj ect of the invention is to provide a novel structure andarrangement whereby the photographic films, during the process ofdevelopment, can be eiiiciently handled and the films developed withgreater speed than is nowpossible when resorting to the customarymethods of developing photographic films.

With the objects above indicated and other objects hereinafter explainedin view, my invention consists in the construction and combination ofelements hereinafter defined and claimed.

Referring to the drawings Fig. 1 is a vertical sectional view taken onso line 1--1 of Fig. 2.

Fig. 2 is a top plan view of the apparatus with the cover removedshowing the arrangement of the developing and fixing tanks and the washWater tank. l

Fig. 3 is a vertical cross sectional view taken on line 3-3 of Fig. 2and showing the manner in which the photographic film is supportedwithin the developing tank.

Fig. 4 is a vertical cross sectional view 90 taken on line 4 4 of Fig. 2and showing the manner in which the wash water tanks are supplied withrunning water.

Fig. 5 is a diagrammatic View of the wiring diagram and therefrigerating unit.

In the drawin s, 10 represents a box-like structure adapte to encloseand support theA entire apparatus which will be described in detail.Thisbox-likestructurewhich is preferably formed of wood has end walls 11of 10U suitable depth and front and back walls 12 and 13, respectively,of suitable length, all securely joined together by nails or othermeans, and having a bottom member 14 also of wood, or other suitablematerial, secured thereto. This box-like structure 10 is supported upona tloor by a plurality of depending legs 15 secured to the underside ofthe bottom member 14. The box-like struc-ture 10 can be of any suitableheight but should be of such a height that a person can convenientlyreach within the interior while developing the photographic films.

Positioned centrally within the box-like structure 10 and spaced apartfrom the walls thereof is a water receptacle 16 supported upon andspaced from the bottom member 14 by a plurality of transverselyextending supporting members 17 which can be secured, respec-tively, tothe bottom member 14 and the receptacle 16, if so desired. The spacebetween the receptacle 16 and the box-like structure 10 is iilled withcork insulation 18, or other suitable insulating material, to reduce, asmuch as possible, temperature changes of the water within the receptacle16 by the surrounding atmosphere. The upper ends of the receptacle 16and the structure l0 terminate in substantially a horizontal plane andare joined together by a horizontally positioned rectangular framemember 19 which closes the opening at the upper portion between the tworeceptacles.

Positioned transversely within the receptacle 16 and supported from therectangular frame 19 are a plurality of tanks, the developing tank beingindicated at 20, the fixing tank by 21 and the wash water tanks by 22.rlhese four tanks are spaced apart and grouped with the developing tank20 and one water wash tank 22 at one end of the receptacle 16, and thefixing tank 21 and the other wash tank 22 at the opposite end of thereceptacle 16. rlhe two water wash tanks are spaced apart suiciently toaccommodate a rerigerating unit 23 suspended within the receptacle 16 bya horizontally extending transverse rod 24 connected to the front andback walls, respectively, of the receptacle 16, and for a purpose whichwill be later described.

The tanks 20, 21 and 22 are of the same construction and are preferablyformed of highly conductive metal having at their upper opposite edgesoutwardly offset portions 25 which are adapted to support frames 26 towhich the photographic iilms are secured, the frames being suspended invertical position, as clearly shown in Fig. 3. The various tanks arewide enough to receive a number of frames containing photographic iilmsand these tanks can be made of any desirable width, depending upon thenumber of films it is desired to handle at any one time. The de-Veloping tank 20 and iixing tank 21 are filled by hand, or otherwise,with develo ing and ixing solutions, respectively, from t e top of thetanks and do not contain any outlet other than the opening in the top ofeach tank. The water wash tanks 22 are provided with inlet openings 28in the bottoms thereof through which water is continuouslyl supplied tothe tanks by a pipe 29, connected to a horizontally extending pipe 30supported in the upper ortion of the receptacle 16 between the end3walls and the developing and fixing tanks 20 and 21. At the fron-t andback ends ofthe pipe 30 are overflow pipes 31 which extend upwardlywithin the receptacle 16 but terminate slightly below the tops of therespective tanks. The water which is introduced into the receptacle 16rises until it reaches the top of the overow pipes 31 which act tomaintain the water within the receptacle 16 at a predetermined level.The water, however, being continually fed into the receptacle 16 resultsin the overiow being carried off through the overow pipes 31, whichcommunicate through the pipes 30 and the pipes 29 with the wash watertanks 22 through the openings 28 in the bottoms of the tanks. The waterwithin the tanks 22 will rise until it reaches the outlet pipes 32secured in the upper portions of the tanks 22 and will be carried offthrough a drain pipe 33 and subsequently through the drain pipe 34 toany suitable sewerage system.

The wash water tanks 22 are provided with independent drains 35connected to the bottom of the tanks and communicating through manuallyoperated valves 36 with a drain pipe 37 leading to the drain pipe 34. Byop eration of the valves 36, the water within the Wash Water tanks 22can be drained out and the system emptied for cleaning or repair. Thereceptacle 16 can likewise be drained through the pipe 37 communicatingthrough the manually operated valve 38 with the drain pipe 37.

The fresh water is fed to the receptacle 16 through a hot water supplyline` 39 and a cold water supply line 40 into a manually controlledmixing chamber 41 having a discharge pipe 42 communicating with a pipe43 through a T-section with the pipe 44 extending down the back of theapparatus and through suitable openings in the back 13 of the boxstructure 10 and receptacle 16 to a position adjacent the coils of therefrigerating unit 23, as clearly shown in Fig. 4. The water. therefore,which is fed into the receptacle 16 is directed against the coils of therefrigerating unit 23. The operation of this refrigerating unit 23 iscontrolled by a thermostat 45 supported in the end of one of theoveriiow pipes 30 and in Contact with the water.

A heating unit 46 is positioned adjacent the Water inlet pipe 44 withinthe receptacle 16 and preferably su ported from the supporting member24. his unit is suitably connected in the circuit which controls theoperation of the refrigerating unit 23 and if: employed to raise thetemperature of the water within the receptacle up to a certain degree.The operation of the unit is controlled by t-he thermostat as, forinstance, when the temperature of the water within the receptacle 16drops a predetermined amount the thermostat 45 is all'ected which causesa switch in the circuit'with the heating unit 46 to be closed and thewater is thereby brought up to the desired temperature.

The thermostat 45 is located within easy reach of the person Working atthe developingr apparat-us and has a portion extending into the end ofthe pipe 3() which receives the water overflow from the receptacle 16.It is therefore apparent that the thermostat is all'ected by the changesin temperature of this Water with which it is in contact and byconnecting the thermostat to a suitable switch in a circuit with a motorconnected to the compressor of the refrigerating unit, the effectiveoperation of the latter' can be c0ntrolled. For instance, if thetl'iermostat is adjusted to maintain the Water within the receptacle 16at a temperature of 65 F., which is the desirable temperature at whichto develop photographie films, any change in the temperature of thewater in the receptacle, due to the fresh incoming water or toatmospheric conditions, will aflect the thermostat to an extent ofeither opening or closing the. switch of the motor circuit, therebycausing operation or non-operation ot' the cornpressor of therefrigerating unit.

In employing the apparatus for the development ot photographic films,the receptacle is continuously supplied with water through the inletpipe`44. When the level of the Water rises to, the overflow pipes 31,the overflow of water is carried ofi therethrough and to the wash watertanks 22 with which the overflow pipes communicate. The water in thetanks 22 reaching the level ot' the outlet pipes 32 passes outtherethrough into the drain 33. Itwill be observed that a continualcirculation of Water around the tanks 20, 21 and 22, through the washWater tanks 22 and thence out of the apparatusby way ot the outlet pipes32 is therefore established.

'lhe circulating water can be maintained at should be understood thatchanges and modifications may be made thereto without dcparting from thespirit of the invention as defined in the appended claims.

Having thus described my invention, I claim: v

1. In an apparatus of the type described, a water receptacle, means forcontinuousl supplying water thereto, a developing tan adapted to containa developing solution and positioned in saidv receptacle in contact withsaid water, a wash water tank positioned in said receptacle, a pipe insaid receptacle communicating with said Wash Water tank for continuouslysupplying said latter tank with Water from vsaid receptacle, means forcarrying ofi' the surplus water from said wash Water tank, and means forautomatically maintaining said water at predetermined temperatures.

2. In an apparatus of the type described, a water receptacle, means forcontinuously supplying water thereto, a developing tank adapted tocontain a. developing solution and positioned in said receptacle incontact with said water, a wash Water tank positioned in saidreceptacle, a pipe in said receptacle communicating with said wash Watertank for continuously supplying said latter tank with water from saidreceptacle, means for carrying ofi' the surplus water from said washWater tank, a temperature control unit in contact with said water, andmeans for automatically actuating said unit upon a change in temperatureof said water.

3. In an apparatus of the type described, a receptacle adapted tocontain water, means for supplying Water thereto, a developing tank, afixing tank, and a wash tank, means for supplying water to said Washtank from said receptacle, each of said tanks being positioned in saidreceptacle and partially submerged in the water, and means formaintaining said water at a predetermined temperature.

4. In an apparatus of the type described, a receptacle, meansfor'continuously supplying Water thereto, a developing tank ofconductive metal positioned in said receptacle in contact with saidWater, a fixing tank positioned in said receptacle in contact with saidwater, a Wash water tank positioned in said receptacle in contact withsaid water and continuously supplied with water from said receptacle,means for carrying off the oversupply of water from said wash watertank, and means for automatically controlling the temperature of saidwater Within said receptacle.

5, In an apparatus of the type described, a receptacle, means forcontinuously supplying Water thereto, a developing tank of conduetivemetal positioned in said receptacle in contact with said water, a,fixing tank positioned in said receptacle in contact with said water, awash water tank positioned in said l tinuously supplying Water to saidreceptacle so as to freely circulate around said tanks,

means for continuously supplying Water to.

said Wash Water tanks from said receptacle, outlets for the Water insaid Wash Water tanks, and means for controlling the temperature of theWater in said receptacle.

7. In an apparatus of the type described, a look-like structure, areceptacle supported therein and insulated therefrom,adeveloping tank, aliking tank, and a Wash Water tank associated with each of said tankssupported in said receptacle, means for continuously1 supplying Water tosaid receptacle so as to freely circulate around i said tanks, means'for continuously supplying Water to said Wash Water tanks from saidreceptacle, out lets for the Water in said Wash Water tanks, atemperature control unit associated with said Water, and means forautomatically actuating` said unit upon a change in degree oftemperature of said Water.

8. In an apparatus of the type described, a receptacle, a developingtank, a fixing tank, and a. Wash Water tank associated with each oitsaid tanks supported in said receptacle, means for continuouslysupplying Water to said receptacle so as tofreely circulatearound saidtanks, means for continuously supplying Water to said Wash water tanksfrom said receptacle, outlets for the Water in said Wash Water tanks, atemperature regulating unit associated with said Water, and meansincluding a thermostat for actuating said unit upon a predetermined dropin the temperature of said water.

9. In an apparatus of the type described, areceptacle, means forcontinuously supplying water thereto, a developing tank positioned insaid receptacle in Contact With said water, a Wash water tank positionedin said receptacle in contact with said Water, conducting means forcontinuously supplying Water to said Wash tank from said receptacle, andcontrol means positioned in said conducting means for automaticallycontrolling the temperature of the Water Within said receptacle.

l0. In an apparatus of the type described, a receptacle, means forcontinuously supplying water thereto, a developing tank posisignature.

GEORGE W. HOPKINS.

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